Ground connector for electric welding



July 26, 1955 H. F. SCHLOETZER GROUND CONNECTOR FOR ELECTRIC WELDING INTOR. Harry E Jch/oefzen Filed May 17, 1954 EIWWH'HMHHII 2,714,198 Patented July 26, 1955 nice GROUND (CONNECTOR FOR ELECTRIQ WELDING Harry F. Schloetzer, Topeka, Kans.

Application May 17, 1954, Serial No. 430,026

3 Claims. (Ci. 339-261) This invention relates to electrical connectors or clamps, and more particularly to such a device for making the ground connection of an electric circuit in electric welding and the like.

It is common practice in electric welding to have one conductor connected to a welding rod holder, and another conductor which serves as a ground connection in the welding circuit is secured by a screw clamp or the like to a portion of the metal being welded. The attaching and removing of such screw clamps is relatively slow and usually requires a wrench or other tool for turning the screw in order to avoid having a loose connection.

The principal objects of my invention are to provide a ground connector which can be quickly and easily adjusted and applied to a wide range of thicknesses of metal plate, rod or like portion of the material to be welded and from a positive grip thereon; to provide a ground connector with a stationary jaw having an electrical conductor connected thereto and a movable jaw with a stub lever coacting with the movable jaw operator for effecting adjustment of the jaws with respect to the work to which the connector is to be attached; to provide such a ground connector with a toggle member and operating handle which cooperate to swing the movable jaw into and out of tight engagement with a work piece to be welded; to provide a ground connector that is quickly and easily applied and removed from a work piece without the use of other tools; and to provide a ground connector for use in electric welding which is economical to manufacture, and is efiicient in use in providing a positive electrical connection with the work piece to be welded.

In accomplishing these and other objects of the present invention I have provided improved details of structure, the preferred form of which is illustrated in the accompanying drawing, wherein:

Fig. 1 is a perspective view of a ground connector embodying the features of the present invention.

Fig. 2 is a side elevational view of the ground connector with the jaws in open position, with portions broken away to illustrate the arrangement of the toggle and jaw operating lever.

Fig. 3 is a view similar to Fig. 2 with the jaw members moved into clamping position with a part to be welded.

Fig. 4 is a transverse sectional view taken on the line 44, Fig. 3.

Fig. 5 is a top view of the ground connector.

Referring more in detail to the drawings:

1 designates a ground connector having a fixed or stationary jaw 2 and a movable jaw 3 disposed substantially in a common plane. The stationary jaw is substantially C shaped and includes a relatively thick bar portion 4 having an upturned forward end 5 terminating in anvil portions 6. An upstanding leg 7 is arranged on the bar portion 4 in rearwardly spaced relation to the anvil 6, said leg preferably being integral with said bar portion. The rearward end of the bar portion remote from the anvil 6 extends beyond the leg 7 and terminates in an enlarged portion or extension 8 which is electrically connected with a ground conductor 9 suitably connected in the electric welding circuit. The anvil 6, bar portion 4 and enlarged portion 8 are preferably formed of copper or other suitable material having good electrical conductivity and are also of suitable cross section to adequately carry a welding current.

The leg 7 extends upwardly from the bar portion 4 or from the same side as the anvil and terminates in an elongated handle member 10 of channel formation extending rearwardly therefrom. The handle 10 includes spaced side walls 11 and 12, with their lower edges connected by a wall 13 to define an upwardly opening channel 14- which extends from the anvil side of the leg 7 to the end of the handle remote from said leg. The handle 10 is arranged above the enlarged portion 8 of the bar 4, and is spaced therefrom sufliciently whereby an operator or welder can easily place a portion of his hand between the handle and conductor 9 in operating the ground connector as later described.

The movable jaw 3 is preferably substantially C-shaped with its open side opposed to the open side of the stationary jaw. The movable jaw has one end 15 pivotally mounted between the side walls 11 and 12 of the handle 16 by a pivoted pin 16 which extends through aligned apertures 17 and 13 in the side walls and movable jaw portion 15 respectively, substantially above the leg 7 of the stationary jaw, the pin 16 being so located that the movable jaw 3 swings thereon to move the free end 19 thereof toward and away from the anvil 6. A lever or handle 20 is pivotally connected by a riveted pin 21 to the movable jaw, the pin 21 being parallel to the pivoted pin 16 and is suitably spaced therefrom whereby the lever 20 is substantially in a common plane with the handle 16. The lever 20 constitutes an operating handle, and is also of channel formation with a downwardly opening channel defined by side walls 22 and 23 which are connected by a top wall 24. A stub lever or bar 25 has one end between the side walls 22 and 23 and pivotally connected thereto by a riveted pin 26, said pin 26 being spaced from the pin 21. The stub lever or bar 25 extends toward the free ends of the handles 10 and 20 and terminates in a tapered end 27 adapted to be selectively engaged in a plurality of serrations 28 of a toothed abutment or fulcrum bar 29 suitably secured to the wall 13 adjacent the free end of the handle member 10. The operating lever or handle 20 and stub lever 25' are cooperating toggle members or sections whereby when the stub lever 25 is in engagement with a serration on the fulcrum bar 29 the operation of the toggle sections swings the movable jaw on its pivot pin 16.

A spring 30 has one end engaging the handle member 29 and the other end engaging the stub lever 25 in spaced relation to the pin 26, whereby said spring urges the end 27 into engagement with the serrations 2% and also urges the handle member 20 away from the handle 19 to effect retraction of the movable jaw 3. A spring 31 has one end connected as at 32 to the movable jaw adjacent the pivot pin 16 and the other end connected as at 33 to the stub lever 25. The spring 31 tends to limit the movement of handle member 20 away from the handle 10 and cooperate with spring 30 in holding the stub lever engaged with the serrations 28. The stub lever 25 and pins 16, 21 and 26 are so arranged that the engagement of the end 27 with a selected serration will stop relative longitudinal movement of the stub lever 25 and handle member 10 before the pivot pin 26 passes by the line between the pin 21 and the end 27 of said stub lever. The serrated bar 29 forms an adjustable abutment or stub lever 25, however, it is believed obvious that other suitable adjustable abutments may be used for adjusting the position of the end 27 of the stub lever and thereby adjust the relative spacing of the jaw members when moved into clamp- .jaw 2.

7 3 ing engagement with a plate 34- or other member to be welded.

In using a ground connector constructed and assembled as described, the lever 20 is swung away from the handle to swing the movable jaw 3 away from the stationary Then the stub lever 25 is moved to engage the end 27 thereof with a serration 28 whereby when the lever is moved toward the handle i it will cause the jaw 3 to move toward the stationary jaw 2 until the spacing therebetween is slightly less than the thickness of the plate 34 or other part to be welded. in other words, the stub lever is adjusted relative to a selected abutment having suitable spacing from the pivot pin 16 to adjust the spacing between the jaws when in clamping position. Then the lever 20 is moved toward the handle 10 compressing the spring 30, which applies pressure holding the stub lever in engagement with the selected abutment serration. This provides a toggle movement that swings the stationary jaw 23 on the pivot pin 16 to the position shown in Fig. 3 wherein the jaws clamp the part to be Welded and hold the anvil 6 in electrical contact therewith. Then when the welding current is turned on and the welding started a circuit is complete from the welding machine to the electrode, through the parts to be welded, bar 4 and conductor 9, back to the welding machine. When it is desired to move the ground connection the lever 20 is moved to repeat the above described operations.

It is believed obvious I have provided a ground connection that is economical to manufacture, positive in operation and that can be quickly and easily applied to and removed from the parts to be welded.

What I claim and desire to secure by Letters Patent is:

l. A ground connector for use in electric welding comprising, a stationary jaw member of relatively high electrical conductivity having a bar portion with a forward end terminating in an anvil portion at one side thereof and a rear end having connection with a ground conductor in a welding circuit, a leg member extending from the bar portion intermediate the ends thereof at the same side as the anvil portion, a handle having one end rigidly connected to the leg member on the stationary jaw and extending rearwardly therefrom, a substantially C-shaped movable jaw disposed substantially in a common plane with the stationary jaw and having one end portion pivot- A.

ally mounted on the stationary jaw adjacent the handle whereby the other end portion is swingable toward the anvil of the stationary jaw, an operating lever having one end pivotally connected to the movable jaw in spaced relation to the pivotal mounting of said jaw and extending rearwardly therefrom substantially in a common plane with the handle, said operating lever having movement toward and away from the handle on the stationary jaw, an abutment member on the handle in spaced relation to the stationary jaw, and a stub lever having one end pivotally connected to the operating lever in spaced relation to the pivotal connection thereof with the movable jaw, the other end of the stub lever being adjustably engaged with the abutment member whereby movement of the operating lever toward the handle swings the said other end portion of the movable jaw toward the anvil on the stationary jaw to a relative spacing determined by the relative spacing of the pivotal mounting of the movable jaw and said other end of the stub lever.

2. A ground connector for use in electric welding comprising, a stationary jaw member of relatively high electrical conductivity having a bar portion with a forward end terminating in an anvil portion at one side thereof and a rear end having connection with a ground conductor in a welding circuit, a leg member extending from the bar portion intermediate the ends thereof at the same side as the anvil portion, a handle having one end rigidly connected to the leg member on the stationary jaw and extending rearwardly therefrom, a substantially C-shaped movable jaw disposed substantially in a common plane with the stationary and having one end portion pivotally mounted on the stationary jaw adjacent the handle whereby the other end portion is swingable toward the anvil of the stationary jaw, an operating lever having one end pivotally connected to the movable jaw in spaced relation to the pivotal mounting of said jaw and extending rearwardly therefrom substantially in a common plane with the handle, said operating lever having movement toward and away from the handle on the stationary jaw, an abutment member on the handle in spaced relation to the stationary jaw, a stub lever having one end pivotally connected to the operating lever in spaced relation to the pivotal connection thereof with the movable jaw, the other end of the stub lever being adjustably engaged with the abutment member whereby said operating lever and stub lever operate as toggles which in response to movement of the operating lever toward the handle swing the said other end portion of the movable jaw toward the anvil on the stationary jaw to a relative spacing determined by the relative spacing of the pivotal mounting of the movable jaw and said other end of the stub lever, and resilient means engaging the operating lever and stub lever to maintain the stub lever in engagement with the abutment member.

3. A ground connector for use in electric welding comprising, a stationary jaw member of relatively high electrical conductivity having a bar portion with a forward end terminating in an anvil portion at one side thereof and a rear end having connection with a ground conductor in a welding circuit, a leg member extending from the bar portion intermediate the ends thereof at the same side as the anvil portion, a handle having one end rigidly connected to the leg member on the stationary jaw and extending rearwardly therefrom, a substantially C-shaped movable jaw disposed substantially in a common plane with the stationary jaw and having one end portion pivotally mounted on the stationary jaw adjacent the handle whereby the other end portion is swingable toward the anvil of the stationary jaw, an operating lever having one end pivotally connected to the movable jaw in spaced relation to the pivotal mounting of said jaw and extending rearwardly therefrom substantially in a common plane with the handle, said operating lever having movement toward and away from the handle on the stationary jaw, an abutment member on the handle in spaced relation to the stationary jaw, stub lever having one end pivotally connected to the operating lever in spaced relation to the pivotal connection thereof with the movable jaw, the other end of the stub lever being adjustably engaged Jiil'l the abutment member whereby said operating lever and stub lever operate as toggles which in response to movement of the operating lever toward the handle swing the said other end portion of the mova le jaw toward the anvil on the stationary jaw to a relative spacing determined by the relative spacing of the pivotal mounting of the movable jaw and said other end of the stub lever, a spring having engagement with the operating lever and stub lever in spaced relation to the pivotal connection thereof to urge said operating lever and stub lever apart, and a second spring having engagement with the movable jaw adjacent the pivotal mounting thereof and with the stub lever intermediate the ends thereof to urge said other end of the stub lever toward the abutment member.

References Cited in the file of this patent UNITED STATES PATENTS 

